Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
Laser systems such as carbon dioxide (CO2) laser systems can be used, for example, in micro-machining applications. Such laser systems can include an amplification medium enclosed within a laser cavity having high reflectivity mirrors such that radiation may be confined between the mirrors at certain frequencies. Light may be confined within the cavity and may grow in amplitude due to the amplification medium. The time of light inside the laser cavity may depend on reflectivity of the mirrors and is an estimate of a quality factor (Q-factor) of the cavity.
Short pulses of laser light can be produced by the laser systems using Q-switching techniques. The laser cavity may be in a lossy state until enough population inversion builds in the laser cavity and may be subsequently switched to a non-lossy state such that stimulated emission can then quickly drain the population inversion in a short time to produce short intense laser light pulses.
In some systems, mechanical components such as rotating cavity mirrors can be used to align the laser cavity for short periods of time. The switching time of such systems can be high owing to time required for the laser cavity alignment. In other systems, certain dye molecules can be placed within the laser cavity, where the dye molecules function as Q-switches for facilitating Q-switching in such systems. In certain examples, crystals of electro-optical materials such as cadmium telluride (CdTe) crystals are placed in the laser cavity of the laser systems. The electro-optical materials are anisotropic and can change polarization of light as it passes through the crystals. Such crystals can be utilized to enable switching of the cavity by applying a high voltage pulse through the crystals.
In some other laser systems, one of the cavity mirrors may be coated with saturable absorber materials such as sulfur hexafluoride (SF6), which can make the mirror reflective once the radiation intensity exceeds a certain level.